In the covert communication, there is always a trade-off between the throughput and covertness. Using a full-duplex receiver offers a two-fold benefit for the covert communication relative to generating AN by a separate and independent jammer. Firstly, it enables a higher degree of control over the transmitted AN signals (e.g., its power), thus causing further deliberate confusion at the warden. Secondly, the cutting-edge self-interference cancellation techniques can be adopted to provide higher data rates for covert communications with the full-duplex receiver.
In [1]}, the transmitter Alice aims to send message at a fixed rate to a legitimate receiver Bob over a fading wireless channel while the whole communication is under the surveillance of the warden Willie. Operating at the full-duplex mode, Bob can receive information from Alice and also simultaneously inject interference to confuse Willie over the same channel, which can increase the detection error probability at Willie. On the other hand, it can also decrease covert throughput due to the effect of self-interference at Bob. Based on these discussions, the trade-off between the achievable rate, the transmission power, and covertness criterion that is the probability of error minimized over all prior distributions of the fading channel was investigated.
